I'm not one for conspiracy theories, and tend to take big media stories with a big pinch of salt, but radon is present in parts of Portland and a genuine hazard. Radon is a naturally occurring gas that tends to collect in confined spaces, such a basements. The Environmental Protection Agency estimates radon causes up to 21,000 cases of lung cancer in non-smokers in the U.S. every year. In Portland, basements abound, as do daylight ranches.
When we bought our home in the West Slope area, we had the downstairs of our daylight ranch tested for radon, since two of our bedrooms were located there. Even though our neighborhood is not in the highest risk areas of town, the test numbers came back high enough to warrant mitigation.
It's a pretty simple process, and at the time was about $1,500. Basically, a hole was created in the slab, a pipe system was inserted into the hole, and a fan pulls the radon out of the home to the outdoors.
The first step is testing. You can buy inexpensive kits online, at Home Depot, or have the home professionally tested. By most accounts the test is most accurate when done over a several day period in an undisturbed area to get the best results. The kit is then sent into a lab (usually part of the cost of the kit) and you can either rest easy or pay some money to rest easy. Isn't that the way it always is? More information.